Sharing of Inter State Transmission Charges and Losses

Transcription

1 Sharing of Inter State Transmission Charges and Losses Implementing Agency National Load Despatch Centre WRLDC,MUMBAI 10 th Nov 16

2 What is PoC Mechanism (1) PoC is a mechanism formulated to determine how the given transmission charges would be shared amongst different generation and load utilities Yearly Transmission Charges for the system are known in advance Charges for transmission system are to be shared amongst the different generation and load utilities

3 What is PoC Mechanism (2) Under PoC mechanism, tariff is specific to a particular point in the network and depends on Specific location of this point in the network The direction of flow from this point (injection / drawl) PoC tariff is different from point to point tariff, as it is independent of the other party to the transaction

4 Desirable Features of a Transmission Pricing Scheme Promote efficient day-to-day operation of Bulk Power Market Signal Locational advantages for investment in Generation & Demand Signal need for Planning and Investment in Transmission System Compensate Owners of existing Transmission Assets Provide Incentive to Transmission Owners to enhance Availability Equitable Sharing among Transmission System Users as per Utilization

5 Desirable Features of a Transmission Pricing Scheme (2) Prevent distortion in Merit-Order Dispatch of Generating Stations Treatment of Transmission Losses Charges known Upfront, retrospective adjustments to be avoided Priority of Transmission System Usage among Users of different categories Simple & Transparent Politically Implementable

6 Historical Background Stage Stage Stage Stage I II III IV Cost of Transmission clubbed with Generation Tariff Implicit Apportioned on the basis of energy drawn (Usage Based) Apportioned on the basis of MW entitlements (Access Based) Hybrid Methodology (Point of Connection) Upto onwards

7 Methods for Sharing of Transmission Charges Postage Stamp Method Contract Path Method MW Mile Method Distance Based Power Flow Based Average Participation Marginal Participation Method Zone to Zone Method Locational Marginal Pricing

8 Pre-PoC Scenario Regional Postage Stamp Method in Long Term Market Contract Path Tariff in Short Term Bilateral Market Point of Connection Tariff in Power Exchanges

9 Drivers for change in Pricing Framework Synchronous integration of Regions- Meshed Grid Increasing complexities in Transmission Changes caused by law and policy Open Access and Competitive Power Markets Pricing Inefficiencies, Market Players concern National Grid / Trans-regional ISGS Changing Network utilization Agreement of beneficiaries a challenge Ab-initio identification beneficiaries difficult

10 Pools and Sub Pools Generator-I Generator-III Load-II WR Pool IPP Pool WR States Pool Load-I IPP Pool UMPP Pool WR States NR States Generator -II Inappropriate Transmission Charge and Loss Sharing Mechanism leads to Suboptimal Transmission Planning

11 Policy Mandate Electricity Act 2003 National Electricity Policy Tariff Policy

12 Policy Mandate National Electricity Policy Section Prior agreement with the beneficiaries would not be a pre-condition for network expansion Section The tariff mechanism would be sensitive to distance, direction and related to quantum of flow.

13 Policy Mandate Tariff Policy Section 7.1 : Transmission Pricing Section The National Electricity Policy mandates that the national tariff framework implemented should be sensitive to distance, direction and related to quantum of power flow Section Transmission charges, under this framework, can be determined on MW per circuit kilometer basis, zonal postage stamp basis, or some other pragmatic variant, the ultimate objective being to get the transmission system users to share the total transmission cost in proportion to their respective utilization of the transmission system Contd..

14 Distance Sensitivity Flow of electricity Based on Laws of Physics Independent of Contract Path Electrical Distance is captured in PoC Mechanism Conductor Impedance Charges of Transmission Lines

15 Direction Sensitivity Chhattisgarh Withdrawal PoC Rate (22.61 Paise/kwh) Injection PoC Rate Paise/kwh) Separate PoC Rates for Withdrawal and Injection Generation Hub High Injection PoC Rate Demand Met from Local Generation Low Withdrawal PoC Rate

16 Quantum Sensitivity Access vs Usage Planning based on Access Usage reflected in PoC Rates Access is reflected in charges payable

17 Advantages of PoC Mechanism National Integration Fulfills Policy Mandate Scientific and elegant way of handling complexities Accommodates Multiple Transmission Licensee Regime Necessary for large capacity corridors Certainty in Transmission Rates Market Friendly Facilitates Competitive Bidding No Pan caking of charges and losses

18 PoC Framework ISTS Licensees DICs NETWORK YTC Injection/ Withdrawal LTA/MTOA I M P L E M E N T I N G A G E N C Y PoC Tariff CTU (Billing, Collection and Disbursement) RPCs (Accounting)

19 Regulatory Initiatives Discussion Paper on Sharing of Charges and losses in Inter-State Transmission System (ISTS) May Approach Paper on Formulating Pricing Methodology for Inter-State Transmission in India Feb Draft Regulation on Sharing of Inter-State Transmission Charges and Losses Jun Regulation on Sharing of Inter-State Transmission Charges and Losses

20 CERC (Sharing of Transmission Charges & Losses) Regulations 2010 Notification of Regulations : 15 th June 2010 Notification of First Amendment: 24 th November 2011 Notification of Second Amendment: 28 th March 2012 Notification of Third Amendment w.e.f: 1 st May 2015 Applicable to: Designated ISTS Customers Inter State Transmission Licensees NLDC, RLDC, SLDCs, and RPCs Regulations came into force from 1 st July 2011 For a period of 5 years unless reviewed or extended by the Commission

21 PoC Methodology in India Point of Connection (PoC) Charges Usage Based Methodology In Rs. per MW per month Nodal / Zonal Charges Separate Injection & Withdrawal Charges To be made known upfront To be applied on Medium Term and Short Term Trades Based on Load Flow Studies Hybrid of Average Participation and Marginal Participation methods Handling Transition To begin with 50% Uniform Charges and 50% PoC Charges Gradual movement towards 100% PoC Charges Three Slab Rates for initial years. From May 15, 9 slabs

22 STU/SEBs/ISTS Licensees Designated ISTS Customers Network Parameters Line wise YTC Nodal Demand / Generation Forecast Injection / Withdrawal Network Parameters Additional Medium Term Injection / Withdrawal Implementing Agency Approved Injection Approved Withdrawal Basic Network Flow Chart for Data Acquisition

23 3 rd Amendment to Sharing Regulations Notified on National Load Despatch Centre

24 Salient Features Peak case Removal of Uniform Charge Introduction of new terms: Reliability Support Charge HVDC Charge Total transmission charge = PoC Charge + HVDC Charge + Reliability Support charge Separate Rate for Long Term and Short Term Transactions Nine slabs Full All India Network (without truncation)

25 25 How to arrive at Approved Injection /Withdrawal Demand Data (for each state/ut): Monthly peak demand met in the last 3 years Average of 3 months peak demand met in each of the last 3 years Forecast based on last 3 year s average of monthly peak demand met Generation Data (for each state/ut): Projected maximum injection, provided by DICs to be vetted by the Implementing Agency based on average of monthly maximum injection in the last 3 years (based on actual metered data available from RLDCs) NLDC

26 26..Contd. For state generators, Maximum injection data (for last 3 years as well as projected for the ensuing quarter) to be provided by respective SLDC. In case of non-submission of data by SLDC Maximum injection of the concerned State shall be taken as the difference between peak met and withdrawal from ISTS based on actual metered data (for the time block corresponding to the block in which peak met occurred). Projected peak demand/forecasted generation of each DIC thus arrived shall be normalized with the projected All-India peak demand met Normalization factor: Projected All India Peak Demand Met Sum of projected demand/gen. for all DICs NLDC

27 Validation Committee To validate Basic Network and Load Flow Results Validation Committee Comprises two officials each from: Implementing Agency National Load Despatch Centre Regional Power Committee Central Transmission Utility Central Electricity Authority Central Electricity Regulatory Commission Nominee from Commission to Chair the Committee

28 Hybrid Methodology Hybrid of Average Participation Marginal Participation NLDC 28 Average Participation:- Power Tracing Used to identify slack (responding) buses for each node Marginal Participation To compute the participation factor of each node on each line.

29 Transmission Pricing in India Before POC Point to point Regime Contract path + Postage stamp After POC Point Of Connection Regime Postage Stamp+ Hybrid Method Only Hybrid Method from Average Participation + Marginal Participation method

30 Transmission Pricing in India Average Participation Run Load Flow considering entire network (limited to certain voltage level) Run Power flow Tracing Generator Tracing to find out slack buses for loads Load Tracing to find out slack buses for generators Marginal Participation Perturb each load by 1 MW. Use slack buses determined from generator tracing. Run load flow. Calculate marginal flow vector for each node. Perturb each generator by 1 MW. Use slack buses determined from load tracing. Run load flow. Calculate marginal price vector Calculate Participation factors Allocate cost to various nodes Formation of prize Zones

31 Information flow chart Basic Network data Nodal Injection & withdrawal Power System Model Load flow on complete network Approved Injection, Approved Drawal, Transmission losses Total YTC, Circuit kms and Indicative Cost Level Generation Zone Demand Zone PoC loss slab for scheduling Generation Zone Demand Zone PoC Slab for billing Point of Connection Loss Average Transmission Charge per ckt kilometer for a voltage level & conductor configuration Point of Connection Transmission Charge YTC assigned to each line Algorithm for computing marginal participation Algorithm for average participation Slack bus List of state lines used as ISTS

32 32 Reliability Support Charge 10 % of the Total Monthly Transmission Charges The Reliability Support Charge Rate, in Rs./MW/Month shall be as under: [10% of the Monthly Transmission Charges of ISTS] [Total Approved Withdrawal of the Withdrawal DICs + Approved Injection of the Generators having LTA to target region] Withdrawal DICs to pay reliability support charge in proportion to their Approved Withdrawal. For Injection DIC having LTA to target region, the charges are payable in proportion to their Approved NLDC Injection

33 33 Treatment of HVDC 10 % of the Monthly Transmission Charges of HVDC Systems to be recovered through Reliability Support Charge Balance 90% payable by Withdrawal DICs of the Region in proportion to their Approved Withdrawal. In case of Injection DICs having Long Term Access to target region, it shall be payable in proportion to their Approved Injection. NLDC

34 34..Contd. Where transmission charges for any HVDC system are to be partly borne by a DIC (injecting DIC or withdrawal DIC, as the case may be) under a PPA or any other arrangement: Transmission charges in proportion to the share of capacity in accordance with PPA or other arrangement shall be borne by such DIC and the charges for balance capacity shall be borne by the remaining DICs by scaling up of YTC of the AC system included in the PoC. NLDC

35 35..Contd. Transmission Charges of Talcher-Kolar HVDC transmission link shall be borne by Withdrawal DICs of the Southern Region in proportion to their Approved Withdrawal Generators having LTA in target region in proportion to their Approved Injection. Transmission charges of Rihand-Dadri and Balia-Bhiwadi HVDC transmission links shall be borne by Withdrawal DICs of Northern Region in proportion to their Approved Withdrawal Generators having LTA in target region in proportion to their Approved Injection. NLDC

36 36..Contd. Transmission charges of Mundra-Mohindergarh HVDC line shall be borne by M/s Adani Power Limited in proportion to its share for transfer of capacity to Haryana (1495 MW). Transmission charges for Balance 1005 MW are to be borne by all the DICs in the country Cost of all HVDC back to back links shall be borne by all the DICs in the country. NLDC

37 Separate Rate for Long term/medium term and Short Term transactions 37 For Long term/medium term: Only withdrawal rates would be calculated and injection rates only for generators having LTA to target region For Short Term: Base case is to be run as earlier (as done prior to 3rd amendment) Injection rate and withdrawal rates are to computed separately NLDC

38 38 Slab Rates For Long term/medium term transactions: Nine Slabs For short term transactions Nine slabs for Injection Rates and nine slabs for withdrawal rates For Transmission losses Nine slabs (in percentage) Slab size of 0.25% subject to minimum loss of 0%. NLDC

39 39 The PoC rate of a DIC is equal to PoC Charge of the DIC LTA/MTOA of the DIC, considered for the quarter Normal Distribution curve obtained:..contd. Rates outside 1 sigma shall be considered as outliers. These rates shall be brought to 1 sigma level. The slab rates lying outside (Mean-1 sigma) shall be brought up to (Mean-1 sigma) and rates above (Mean +1 sigma) shall be brought down to (Mean+1 sigma). In case of underrecovery or over-recovery, all the rates shall be scaled up or scaled NLDC down as the case may be.

40 Zoning Criteria for Zoning of nodes: Regulations7(1)(t) Zones shall contain relevant nodes with Costs in the same range Nodes within zones shall be combined in a manner that they are Geographically & electrically proximate; Demand zones within Geographical boundary of State ISGS connected to 400kV Inter State Transmission System to be taken as separate zone For Merchant Power Plant connected to 400kV ISTS, entire merchant Capacity + LTA to be considered for computing Injection PoC Rate Demand zones : State Control Area Zonal Charges : Weighted Average of Nodal Charges Revision of Zones in a financial year Significant Changes in Power System Prior approval from commission by IA Annexure, Clause 2.2 Regulations7(1)(t)(vi)

41 41 NLDC PoC Charges and Losses Application Periods July 2011 March 2012 April 2012 September 2012 October 2012 March 2013 April 2013 June 2013 onwards Quarterly computation.

42 POC losses Computation Point of Connection Losses Independent of Contract Path 50% losses through Hybrid Method and 50% through Uniform Loss Allocation Mechanism upto Apr % PoC losses through Hybrid methodology from May15. Moderation of Losses Based on Actual Regional Losses of last week and Losses based on studies 16-Nov-16 र ष ट र य भ र प र षण क द र 42

43 PoC Loss Computation (2) Output of System Studies MW Losses of each node Loss Allocation Factor Weighted average losses (%) for each region Zonal Loss : Weighted Average of losses at each node Moderation of Zonal Losses One PoC Loss for each entity per week 16-Nov-16 र ष ट र य भ र प र षण क द र 43

44 Moderation of Losses (1) Need of Moderation Difference in actual and study scenarios Correct computation of injection and drawal schedule of various utilities. Scheduled losses to be closer to actual losses in the system so that system mismatch is avoided. Minimizing the mismatch between UI payable and receivable Moderation at regional Level Moderation Factor = Actual Losses of previous week (A act ) ( In %) Regional Losses based on Studies (A s )(In %) 16-Nov-16 र ष ट र य भ र प र षण क द र 44

45 Application of Losses in Scheduling PoC Losses Slab I V +1.00% II V +0.75% III V +0.50% IV V +0.25% V Average Loss VI V -0.25% VII V -0.50% VIII V -0.75% IX V -1.00% Loss to be applied on each regional entity Drawee Entity to bear full losses for : Long Term Transactions Injecting Entity and Drawee Entity to share losses for: Short Term Transaction Collective Transactions Bilateral Transactions % of Losses I V +1.00% II V +0.75% III V +0.50% IV V +0.25% V Average Loss VI V -0.25% VII V -0.50% VIII V -0.75% IX V -1.00%

46 Accounting Billing and Collection of Charges Accounting of Charges : Monthly accounts in each region shall be prepared by respective RPC Regulation 10(1) Regional Power Committee Regional Transmission Accounts (Next Working Day of Issue of Regional Energy Account for the previous Month) Regional Transmission Deviation Accounts (15 th Day of Every Month for the previous Month)

47 Accounting Billing and Collection of Charges Billing : Central Transmission Utility (CTU) shall be responsible for Raising the bills, collection and disbursement to ISTS licensees based on Accounts issued by RPC Regulation 11(1) Bill to be raised only on DIC s SEB/STU may recover such charges from DISCOMs, Generators and Bulk Consumers connected to the intra-state system. Regulation 11(2) The billing from CTU for ISTS charges for all DICs shall be : In 3 parts on the basis of Rs/MW/Month and; the fourth part for deviations would be on the basis of Rs/MW/Block Regulation 11(3)(7)

48 Accounting Billing and Collection of Charges Central Transmission Utility First Part (Based on Approved Injection/Withdrawal and PoC Rate) Second Part (Recovery of Charges for Additional Medium Term Open Access) Third Part (Adjustments Based on FERV,Interest, Rescheduling of Commissioning) Fourth Part (Deviations) Next Working Day of uploading of RTA for previous month Along with First Part Biannually (1 st Day of September and March 18 th Day of a Month

49 Information Procedures Information on Public Domain by IA For username/password, please write to Latest result..\..\ q3\poc Rates and Losses Order for _Oct- Dec(Q3)_ pdf Regulation 17

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